Towards Adaptive Service Ecosystems with Agreement Technologies

The growing complexity of software is emphasizing the need for systems that have autonomy, robustness and adaptability among their most important features. Hence, their development and maintenance strategies must be redesigned. Humans should be relieved from an important part of these tasks, which should be performed by systems themselves; self-adaptation can be therefore considered as an architecture-level concern. Service-oriented architectures, and in particular service ecosystems as their more dynamic variant, show a higher degree of adaptivity and flexibility than many other alternatives. In this context, Agreement Technologies (AT) appears as a service-oriented, architecture-aware evolutions of Multi-Agent Systems, which themselves are self-aware structures conceived to solve generic problems. However, they still do not provide mechanisms to change their composition patterns and element types, which are necessary to achieve real self-adaptivity. This work proposes an architectural solution for it: the required dynamism will be supported by an emergent agreement - an evolving architectural structure based on combining predefined controls and protocols. These are handled in the context of the service-oriented, agent-based and organization-centric framework defined by AT, and implemented within the THOMAS platform. This work provides the first architectural abstractions to support this emergent structure. A real-world example showing the interest of this approach is also provided, and some conclusions about its applicability are finally outlined.